Conveyor belt with code elements



p 27, 1966 D. c. PROSSER ETAL 3,275,123

CONVEYOR BELT WITH CODE ELEMENTS Filed Feb. 27, 1963 INVENTORS. 0,414063 P205862 $0605 A pa/v/v/xve, (/2

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United States Patent 3,275,123 CONVEYOR BELT WITH CODE ELEMENTS David C.Prosser, Minuetonka Village, and Jacob A. Ronning, Jr., Wayzata, Minn,assignors, by mesne assignments, to Cutler-Hammer, Inc., a corporationof Delaware Filed Feb. 27, 1963, Ser. No. 261,323 2 Claims. (Cl. 198-38)This invention relates to the field of conveyor belt construction andmore particularly to conveyor belts which contain code retainingelements.

It is generally well known that conveyor belts are made in numerous waysand of various constructions. Certain conveyor belts are designed toconvey loads which are extremely high in temperature and others aredesigned to operate in the opposite temperature conditions, that is, infreezing weather. Also, conveyor belts have been designed so that theywill more nearly conform to concave rollers which are used therewith toreduce spillage. Numerous means have been used to strengthen belts toprolong their wear and usefulness. belts have used wire mesh or lengthsof wire running longitudinally with the belt or across the belt toimprove the particular operating characteristics desirable in theapplication for which the belt is to be used.

However, when belts of various types of construction containing metallicelements are subjected to magnetic fields to produce a code therein, thebelts which are thus far available have not proven to be satisfactorycarriers of the magnetic codes. Magnetic code apparatus combined withconveyor systems such as this, is found in Wales et a]. Patent3,075,653, entiled Apparatus for and Method .of Identifying Material. Ithas been found that numerous disadvantages are present when the codedetecting apparatus tries to detect a code which is carried by a portionof a longitudinal wire or metallic member in a belt or in a wire whichextends perpendicular to the direction of motion of the belt. That is,the magnetic field tends to distribute itself along the entire metallicconductor and if magnetic fields are placed at different locations alongthe same magnetic code bearing wire or element, there are instancesWhere a new code is created or the code decays to a point where itbecomes unintelligible. It should also be kept in mind that by addingwire or metal to the belt, the belt itself is generally not strengthenedin any manner since the material merely surrounds the elements and theyprovide points of discontinuity running entirely across the belt orlongitudinally with the belt. In fact, some attempts have been made toimprove the construction of the belts by using plastic threads or cablesalong the warp of the belt and using metallic elements such as wire inthe woof of the belt. Such an arrangement has the disadvantages justdescribed when used with magnetic coding systems. These arrangements ofthe code heating elements prove to be even more inadequate when a codepattern is used involving a trinary mathematical system. That is, thetrinary system as used herein refers to the situation where the magneticcode may either be polarized North-South, South-North, or contain nomagnetic polarity. In using this type of coding arrangement, there willbe instances where the code area should contain no magnetic signal andthe types of belts available heretofore which contain magnetic retainingmaterials will generally produce some magnetic field in the area wherenone should appear and thereby produce an erroneous signal to thesensing equipment.

The present invention contemplates confining the code areas to a bitarea so that a magnetic state of the area is reliable and will produce astronger magnetic :Many of the p ice pulse in the sensing equipment forthe shorter bit material. More important is the fact that the cross-talkbetween the magnetic areas is almost eliminated since the code area bitsare spatially removed from each other so that magnetic isolation betweencode channels is effectively accomplished. The so-called bit areas maytake on several forms and configurations, some of which will bedescribed in more detail hereinafter. By using materials such as wirestaples, small metallic strips or any other material capable ofretaining a magnetic field and capable of having the field changed whichcan be secured to the webbing which forms the belt, such a bit area isproduced. It has also been found that by using the materials such as thewire staples or small metallic strips secured to the webbing which formsthe belt, the sensing equipment will tolerate more side sway of the beltand thus prove to be more reliable. In fact, the manufacturing of thebelt is made much more simple for use with the code sensing equipmentwhere the small metallic elements are used and the belts may then be cutto the desired widths without further trimming of protruding wires onthe edges of the belt which is common to those using transverse directedcables or wires.

Another conguration of the material which will retain the magnetic codeis one in which the material is formed in a shape similar to analternating current wave form. That is, the material extends in the longdirection of the belt in at least one row or more, but each row alsoprovides short transverse sections of the material which areinterconnected between adjacent ends, having been formed of a continuouspiece of material or in a continuous manner. Also, for some applicationsit may also be desirable to form the magnetizable elements from stripsof natural or synthetic chemical compounds which have alternate areas ofmagnetic properties and non-magnetic properties. That is, the stripswill form an integral part of the belt in such a manner that columns androws of code retaining areas are created in the belt. Such areas mayalso be created by coating the material on the plies and forming thebelt by conventional means.

It is contemplated that some applications of the invention will requirethat certain columns be devoid of a magnetic code retaining area. Inother words, one

column will contain three such areas, while the next column will containmagnetic code areas in two rows while the next column will containmagnetic code areas in two rows different from that in the precedingcolumn,

by way of example, or any other combination desired.

It is therefore a general object of this invention to provide a novelconveyor belt for use with magnetic coding apparatus. 7

It is yet another object of the present invention to provide a conveyorbelt with reduced metal content and thereby provide a belt with lessmass and more flexibility.

It is yet another object of this invention to provide a conveyor beltfor use with magnetic coding and sensing equipment having improvedbonding of the belt because of reduced metal content.

It is still a further object of the present invention to provide aconveyor belt having magnetic code retaining elements formed therewith.

It is still a more specific object of the present invention to provide aconveyor belt having magnetic code retaining elements secured betweenplies of the fabric forming the body of a belt.

It is still another object of this invention to provide a conveyor belthaving a plurality of magnetic code retaining elements all of which arespaced one from the other.

member.

It is yet another object of this invention to provide a conveyor belthaving magnetic code retaining elements formed in columns and rows inthe plane of the belt.

These and other objects and advantages of this invention will more fullyappear from the following description, taken in connection with theaccompanying drawings, wherein like reference characters refer to thesame or similar parts throughout the several views, and in which:

FIG. 1 is a cut-away view of a belt section having code retainingelements showing relative placement of the belt with respect todetection and diverter equipment; and

FIG. 2 is another cut-away view of' a belt section showing another formof code element and means for securing it to the belt.

In FIG. 1, a section of a conveyor belt is shown. Belt 10 is showngenerally as a section of a fiat endless conveyor belt and it isgenerally known that such belts are made to conform to the idler rollsor rollers over' The belt is formed from three.

shown, ply 12 is sandwiched between lower ply 11 and.

upper ply 13. It should also be understood that the belt may contain asingle'ply or numerous plies of materialdepending upon the requirementsof the belt. Se-

cured to ply 12, is a plurality of staples 14 whichare formed into threerows designated A, B, and .C. It will also be seen that the staples 14are formed in columns such as columns I, H, III, IV, and V. In otherwords, staples 14 form a pattern designated such as row A, column II.The spacing in each of the rows between the staples may be equal asshown, or staggered, and

isolation from each other. The staples may besecured to one of the pliesor several of the plies and may actually be secured where onewillappear. in one of the plies, another row in a second. ply, and athird one in another ply. The different plies of reinforcing materialare a tension resisting material such as woven fabrics made of cotton,rayon, nylon, glass fiberor the like which do not contain magnetic fieldretaining properties.

To complete the belt, an elastic non-magnetic material 15 completelyencircles and impregnates the plies 11,12,

4 10 to be diverted from the belt 10. The detecting structure andassociated apparatus do not form a part of the invention per se butdemonstrate the use of the belt in its cooperating capacity to providethe correct magnetic code for diversion of an article. Of course, therewould be as many sensing heads as are required for the particular codepatterns. v

In some. instances, it may be more desirable to use small -metallicstrips such as strips 21 and secure them to ply 12 by other suitablemeans such as a rubber'coating or cement-22 which will bond with thevulcanized non-magnetic material 15 surrounding the plies andimpregnating the plies. 1 1, 12, and 13. It will be noted that the samecolumn and row arrangement is used'as shown in FIG. 1. The method ofmanufacturing the belt by the use of the present construction ismade'uncomplicated by the fact that the ply containing the code bearingelements may be formed first and merely drawn, from a roll of materialbearing the elements, between two other plies of material and the entireunit sandwiched into a belt by the vulcanizing or other suitableprocess. It should also be kept, in mind that the metal staples 14 orcode bearing elements 21 maybe fixedly secured to the elastic materialshould it be desirable to locate the staples or elements upon ply 13.

From the foregoing description and disclosure it will be seen that a newmeans of providing a conveyor belt for use withimagnetic coding anddetecting apparatus has been set forth. It will also be apparent that,by the use of the construction shown and described herein, the conveyorbelt is not weakened by an excessive amount of metal contained withinthe belt. Furthermore, by

, the use of the appropriate spacing of the code retainand 13 ofreinforcing fabric so that the entire :struc- I a the staples 14 orother suitable elements placed on the sheet in the same relativepositions. as described above, and then folded over eachother and theplurality of plies stitched together to form one load bearing belt Ofcourse, other variations of the. belt may be formed by stitching severalseparate plies together, any one or all of which has the staples 14fastened thereto or covering a single ply containing the staples 14 withanother sheet encircling the single ply. Thus in this manner, aninexpensive belt may be formed which will operate satisfactorily with acode detecting apparatus.

In order. to detect the code appearing in staples or other similarelements 14, an oscillator 16 provides excitation :to a sensing head 17.Upon sensing head 17 ing elements, an improved magnetic field may bedetected which has virtually no cross-talk between .the magneticelements. It has also been shown that a particular belt construction, isset forth which is particularly well adapted to provide a magnetic codewhen used with the trinary mathematical system. 7

It will, of course, beunderstood that various changes may be made in theform, details, arrangement and proportions of the parts withoutdeparting from the scope of this invention which consists of the mattershown and described herein and set forth in the appended claims. I

What is claimed is: v

1. An endless conveyor belt for extending over a conveyor'frame anddriving mechanism and for .use with magnetic coding and detectingapparatus comprising:

(a) a plurality of flat plies of reinforcing non-magnetic woven fabricforming an endless body of tension resisting material having flexibilityand adapted for cooperatively engaging the conveyor frame and drivingmechanism; 7

(b) a plurality of separated magnetic code retaining 7 elements spacedapart 'so that each is capable of being magnetized with a portion of acode and-retaining a magnetic field for codejsensing purposes untildemagnetized, said elements fixedly secured to atleast one of said pliesof fabric and arranged in (c) and an elastic non-magnetic materialcompletely encircling and impregnating said plurality of plies of fabricto form a laminated belt with said code retaining elements completelyembedded therein.

2. The invention as set forth in claim 1 wherein all of said coderetaining elements are disposed withthe longer 5 6 dimension of each ofsaid elongate shapes parallel to that FOREIGN PATENTS of all others-1,270,105 7/1961 France.

751,689 7/1956 Great Britain. References Cited by the Examiner 5 OTHERREFERENCES UNITED STATES PATENTS Maico Publication: The Basic MahrolSystem, P. D. 1 5 21 1 192 1 Sheet No. 103, June 1, 1960. 2 857 05910/1958 Goerlich.

y 1 L N P 7 3075653 H1963 W ales 198 38 EVON B U rlmwy Exammel 10WILLIAM B. LABORDE, SAMUEL F. COLEMAN,

3,084,784 4/1963 Zoubek 198 Examzners.

3179241 4/1965 R. E. AEGERTER, Assistant Examiner.

1. AN ENDLESS CONVEYOR BELT FOR EXTENDING OVER A CONVEYOR FRAME ANDDRIVING MECHANISM AND FOR USE WITH MAGNETIC CODING AND DETECTINGAPPARATUS COMPRISING: (A) A PLURALITY OF FLAT PLIES OF REINFORCINGNON-MAGNETIC WOVEN FABRIC FORMING AN ENDLESS BODY OF TENSION RESISTINGMATERIAL HAVING FLEXIBILITY AND ADAPTED FOR COOPERATIVELY ENGAGING THECONVEYOR FRAME AND DRIVING MECHANISM; (B) A PLURALITY OF SEPARATEDMAGNETIC CODE RETAINING ELEMENTS SPACED APART SO THAT EACH IS CAPABLE OFBEING MAGNETIZED WITH A PORTION OF A CODE AND RETAINING A MAGNETIC FIELDFOR CODE SENSING PURPOSES UNTIL DEMAGNETIZED, SAID ELEMENTS FIXEDLYSECURED TO AT LEAST ONE OF SAID PLIES OF FABRIC AND ARRANGED IN AT LEASTONE NON-CONTINUOUS ROW EXTENDING LONGI-